Many courier companies offer to pick up and deliver packages on behalf of their customers. In exchange for delivering the packages to the customer's specified destination, the courier company charges a fee. Typically the fee is based upon one or more of the size of the package, the weight of the package, the destination of the package and the urgency of the packages' delivery. Larger courier companies typically have a central sorting station. At the central sorting station packages picked up from customers are processed for delivery to the customer's specified destination.
A problem exists in determining the appropriate charge for the customer to delivery the package. In some cases, the volume of the package is the limiting constraint, especially for goods shipped by overnight air carrier. In other circumstances, the packages' weight can be the limiting factor again for example, when being shipped by air carrier. What is needed is a way of measuring a package to evaluate the appropriate shipping charge for the customer.
In the past several attempts have been made to develop such measuring devices. For example, U.S. Pat. Nos. 5,469,262 and 6,201,604 provide non-destructive remote volume measuring of packages using light beams. However, the sensing mechanisms involved are complex and expensive. This renders such devices beyond the reach of all but large courier companies.
U.S. Pat. No. 2,708,368 presents a less expensive alternative, which involves a person who places the package on an electronic measuring grid. The worker pushes the package against the grid, where it contacts trip switches. The switches are located on an x, y and z axes and a size measurement is obtained by measuring, in effect, how many switches are tripped, by direct contact between the package and the switches along each axis. However, such direct contact measuring is unreliable since most packages to be shipped are made from flexible packaging material, such as cardboard. Such flexible packaging material can soften or deform under impact and any number of switches along a packages length may not be tripped yielding a false (low) reading. Further, physical contact trip switches involve moving parts which can wear out over time, which can get gummed up and stick in an on or off position by dirt, debris or the like, and which are otherwise expensive to maintain and operate. Further, the need for a person to orient the package on the grid for measurement is expensive. Lastly, there is no way to detect whether the volume measured is at all accurate.
What is needed is a simple and reliable system for measuring the volume of a package, commonly known as “cubing” a package, and for weighing a package to determine an appropriate shipping charge.